TasP

Recent advances in ART have improved the success of treating infected individuals and have provided valuable tools to prevent infection. Early ART also offers one of the most practicable components in attempting to achieve functional cures, but diagnosing and treating HIV early remains a challenge.

Early initiation of antiretroviral therapy (ART) significantly improves the survival of people living with HIV (PLWH) and reduces HIV transmission to uninfected partners. Mathematical models suggest that treatment-as-prevention programmes could lead to HIV elimination. How the clinical efficacy of ART in preventing HIV transmission translates to real-life settings depends in large part on the capacity of HIV programmes to engage and retain PLWH. The effects of ART on HIV incidence may also depend on changes in sexual network dynamics during the course of ART scale-up which are discussed in this article.

In recent years, scientific innovations in HIV control have expanded the range of available interventions – male circumcision, topical microbicides, oral pre-exposure prophylaxis (PrEP) and treatment as prevention (TasP) have all sparked significant interest due to their potential effectiveness and versatility. While all these options are potentially available, resources remain limited and choosing which interventions to implement at scale is a difficult task, given the complex nature of disease transmission, the impact of behaviour in epidemic dynamics, and the different costs of these programs. Here we analyse the effects of scaling up PrEP and ART for HIV prevention in South Africa, to help decision makers understand how these interventions would work if considered independently or in combination.

In order to assess the effects of Treatment as Prevention (TaP) on HIV incidence, results from HIV testing over time need to be available. This links to two aspects of information retention – data storage and data usage – which are discussed and illustrated by the case of HIV testing data in this editorial.

The year is rushing to a close. World Aids Day is around the corner, and from our vantage point at SACEMA, 2011 is likely to be remembered as the year in which the concept of Treatment as Prevention (TasP) stopped being controversial. Few now seriously express doubt that effective ARV treatment cuts transmission, and debate has moved on to grapple with the questions of the extent, and over what time scale, this can translate into ‘game changing’ or ‘paradigm shifting’ scenarios.